Background and Objectives <p>Microplastics are pervasive environmental pollutants, attracting significant concern due to their potential adverse effects on ecosystems and human health. This study hypothesizes that microplastics may significantly impact gastrointestinal (GI) health through various mechanisms. The objective of this systematic review is to explore the effects of microplastics on GI health, focusing on animal models such as mice, fish and earthworms.</p> Methods <p>A systematic review approach was employed, analyzing studies that investigate the impact of microplastics on the gut microbiota, gut barrier integrity and GI inflammation. The review includes a synthesis of findings from multiple animal models.</p> Results <p>The review reveals consistent evidence that microplastics can disrupt the gut microbiota, impair the gut barrier, and induce inflammatory responses in the GI tract. Statistical analysis shows a significant correlation between microplastic exposure and GI health deterioration across various animal models.</p> Conclusions <p>The findings underscore the harmful effects of microplastics on GI health, emphasizing the urgent need for policy interventions to reduce plastic pollution. Implementing measures to limit the production and usage of disposable plastics is crucial for mitigating the risks posed by microplastic contamination to promote environmental sustainability and safeguard human well-being.&#xa0;</p> Graphical Abstract <p></p>